Featured Research

 

Ghost Forests

The earth is getting warmer, sea levels are rising, and this is reflected in the occurrence of “ghost forests” in the Mullica Valley in southern New Jersey. The increase is obvious in most of our lifetimes and especially since Superstorm Sandy, when salty water was pushed far upstream. One result was the death of many trees, especially those that usually grow in freshwater bogs such as Atlantic white cedar. Once exposed, even for a few tidal cycles, they die, but remain standing because they are very rot resistant.

Photograph of transition from living Atlantic white cedars in background to standing dead Atlantic white cedars in front of them, and Phragmites marsh invading the forest along a small stream, a tributary of Nacote Creek, at Riverside Road in Port Republic.

This rot resistance, plus long-term burial in sediments, preserves a record of their occurrence, even over thousands of years which is being studied in this collaborative effort with Drs. Ken Able, Ben Horton and Ph.D. graduate student Jennifer Walker. The ancient “ghost forests” are evident from shallow tributaries in the Mullica Valley at low tide from a kayak

Exposed ancient ghost forest of Atlantic white cedar stumps and logs at low tide in the Otter Pond at Big Creek near Port Republic in the Mullica River.

and with sidescan sonar at deeper depths in the Mullica River (to 15 ft).

Submerged Atlantic white cedar (stumps and logs) density determined by sidescan sonar observations south of Hog Islands in the Mullica River. Transects made by boat are shown as red lines.

Radiocarbon dates from Atlantic white cedar samples from salt water and intertidal and subtidal creeks verify the occurrence of these trees from the 5th to 16th centuries. Thus, they grew (sometimes for hundreds of years) and they were exposed to rising sea levels, especially since the Industrial Revolution, as sea levels have risen.